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Pablo Carranza Velez 95bbe6ea49 Add a /v1/healthy endpoint that fails if the supervisor is unhealthy, and a HEALTHCHECK command to the Dockerfile that uses it

We add an endpoint to the supervisor API that checks the following conditions to determine whether the supervisor is healthy:
* That the update cycle has run fully, in a time that's less than twice the poll interval. Unless we're downloading an image, in which case
we assume it's healthy (otherwise we'd get into the issue of determining a reasonable timeout for the image download, which is already done in a configurable way with delta options and the like).
* That the current state report to the Resin API hasn't failed more than 3 times. Unless the device has no connectivity, or the connectivity check is disabled, in which case we don't know
if the report failed simply because there's no network.
* That the gosuper component is working (since we periodically hit its API to get the IP addresses, we mark it as not working if this API call fails).

We need this endpoint to be unauthenticated for the docker daemon to be able to hit it (though, as the rest of the API, it is protected with iptables rules).

Change-Type: minor
Signed-off-by: Pablo Carranza Velez <pablo@resin.io>

2017-12-11 00:11:56 -08:00

15 KiB

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Interacting with the Resin Supervisor

The Resin Supervisor is resin.io's agent that runs on devices. Its main role is to ensure your app is running, and keep communications with the Resin API server.

The Supervisor itself has its own API, with means for user applications to communicate and execute some special actions that affect the host OS or the application itself. There are two main ways for the application to interact with the Supervisor: the update lockfile and the HTTP API.

Only Supervisors after version 1.1.0 have this functionality, and some of the endpoints appeared in later versions (we've noted it down where this is the case). Supervisor version 1.1.0 corresponds to OS images downloaded after October 14th 2015.

HTTP API reference

The supervisor exposes an HTTP API on port 48484 (RESIN_SUPERVISOR_PORT).

All endpoints require an apikey parameter, which is exposed to the application as RESIN_SUPERVISOR_API_KEY.

The full address for the API, i.e. "http://127.0.0.1:48484", is available as RESIN_SUPERVISOR_ADDRESS. Always use these variables when communicating via the API, since address and port could change.

Alternatively, the Resin API (api.resin.io) has a proxy endpoint at POST /supervisor/<url> (where <url> is one of the API URLs described below) from which you can send API commands to the supervisor remotely, using your Auth Token instead of your API key. Commands sent through the proxy require an appId and/or deviceId parameter in the body, and default to POST requests unless you specify a method parameter (e.g. "GET").

The API is versioned (currently at v1), except for /ping.

You might notice that the formats of some responses differ. This is because they were implemented later, and in Go instead of node.js.

Here's the full list of endpoints implemented so far. In all examples, replace everything between < > for the corresponding values.

GET /ping

Responds with a simple "OK", signaling that the supervisor is alive and well.

Examples:

From the app on the device:

$ curl -X GET --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/ping?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

OK

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "method": "GET"}' \
	"https://api.resin.io/supervisor/ping"

POST /v1/blink

Starts a blink pattern on a LED for 15 seconds, if your device has one. Responds with an empty 200 response. It implements the "identify device" feature from the dashboard.

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/blink?apikey=$RESIN_SUPERVISOR_API_KEY"

(Empty response)

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/blink"

POST /v1/update

Triggers an update check on the supervisor. Optionally, forces an update when updates are locked.

Responds with an empty 204 (No Content) response.

Request body

Can be a JSON object with a force property. If this property is true, the update lock will be overridden.

{
	"force": true
}

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	--data '{"force": true}' \
	"$RESIN_SUPERVISOR_ADDRESS/v1/update?apikey=$RESIN_SUPERVISOR_API_KEY"

(Empty response)

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "data": {"force": true}}' \
	"https://api.resin.io/supervisor/v1/update"

POST /v1/reboot

Reboots the device

When successful, responds with 202 accepted and a JSON object:

{
	"Data": "OK",
	"Error": ""
}

(This is implemented in Go)

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/reboot?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"Data":"OK","Error":""}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/reboot"

POST /v1/shutdown

Dangerous. Shuts down the device.

When successful, responds with 202 accepted and a JSON object:

{
	"Data": "OK",
	"Error": ""
}

(This is implemented in Go)

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/shutdown?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"Data":"OK","Error":""}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/shutdown"

POST /v1/purge

Clears the user application's /data folder.

When successful, responds with 200 and a JSON object:

{
	"Data": "OK",
	"Error": ""
}

(This is implemented in Go)

Request body

Has to be a JSON object with an appId property, corresponding to the ID of the application the device is running.

Example:

{
	"appId": 2167
}

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	--data '{"appId": <appId>}' \
	"$RESIN_SUPERVISOR_ADDRESS/v1/purge?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"Data":"OK","Error":""}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "data": {"appId": <appId>}}' \
	"https://api.resin.io/supervisor/v1/purge"

POST /v1/restart

Restarts a user application container

When successful, responds with 200 and an "OK"

Request body

Has to be a JSON object with an appId property, corresponding to the ID of the application the device is running.

Example:

{
	"appId": 2167
}

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	--data '{"appId": <appId>}' \
	"$RESIN_SUPERVISOR_ADDRESS/v1/restart?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

OK

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "data": {"appId": <appId>}}' \
	"https://api.resin.io/supervisor/v1/restart"

POST /v1/tcp-ping

When the device's connection to the Resin VPN is down, by default the device performs a TCP ping heartbeat to check for connectivity. This endpoint enables such TCP ping in case it has been disabled (see DELETE /v1/tcp-ping).

When successful, responds with an empty 204:

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/tcp-ping?apikey=$RESIN_SUPERVISOR_API_KEY"

(Empty response)

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/tcp-ping"

DELETE /v1/tcp-ping

When the device's connection to the Resin VPN is down, by default the device performs a TCP ping heartbeat to check for connectivity. This endpoint disables such TCP ping.

When successful, responds with an empty 204:

Examples:

From the app on the device:

$ curl -X DELETE --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/tcp-ping?apikey=$RESIN_SUPERVISOR_API_KEY"

(Empty response)

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "method": "DELETE"}' \
	"https://api.resin.io/supervisor/v1/tcp-ping"

POST /v1/regenerate-api-key

Invalidates the current RESIN_SUPERVISOR_API_KEY and generates a new one. Responds with the new API key, but the application will be restarted on the next update cycle to update the API key environment variable.

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/regenerate-api-key?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

480af7bb8a9cf56de8a1e295f0d50e6b3bb46676aaddbf4103aa43cb57039364

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/regenerate-api-key"

GET /v1/device

Introduced in supervisor v1.6. Returns the current device state, as reported to the Resin API and with some extra fields added to allow control over pending/locked updates. The state is a JSON object that contains some or all of the following:

api_port: Port on which the supervisor is listening.
commit: Hash of the current commit of the application that is running.
ip_address: Space-separated list of IP addresses of the device.
status: Status of the device regarding the app, as a string, i.e. "Stopping", "Starting", "Downloading", "Installing", "Idle".
download_progress: Amount of the application image that has been downloaded, expressed as a percentage. If the update has already been downloaded, this will be null.
os_version: Version of the host OS running on the device.
supervisor_version: Version of the supervisor running on the device.
update_pending: This one is not reported to the Resin API. It's a boolean that will be true if the supervisor has detected there is a pending update.
update_downloaded: Not reported to the Resin API either. Boolean that will be true if a pending update has already been downloaded.
update_failed: Not reported to the Resin API. Boolean that will be true if the supervisor has tried to apply a pending update but failed (i.e. if the app was locked, there was a network failure or anything else went wrong).

Other attributes may be added in the future, and some may be missing or null if they haven't been set yet.

Examples:

From the app on the device:

$ curl -X GET --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/device?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"api_port":48484,"ip_address":"192.168.0.114 10.42.0.3","commit":"414e65cd378a69a96f403b75f14b40b55856f860","status":"Downloading","download_progress":84,"os_version":"Resin OS 1.0.4 (fido)","supervisor_version":"1.6.0","update_pending":true,"update_downloaded":false,"update_failed":false}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "method": "GET"}' \
	"https://api.resin.io/supervisor/v1/device"

POST /v1/apps/:appId/stop

Introduced in supervisor v1.8. Temporarily stops a user application container. A reboot or supervisor restart will cause the container to start again. The container is not removed with this endpoint.

When successful, responds with 200 and the Id of the stopped container.

The appId must be specified in the URL.

Request body

Can contain a force property, which if set to true will cause the update lock to be overridden.

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/apps/<appId>/stop?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"containerId":"5f4d4a857742e9ecac505ba5710834d3852ad7d71e10389fc6f61d8655a21806"}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/apps/<appId>/stop"

POST /v1/apps/:appId/start

Introduced in supervisor v1.8. Starts a user application container, usually after it has been stopped with /v1/stop.

When successful, responds with 200 and the Id of the started container.

The appId must be specified in the URL.

Examples:

From the app on the device:

$ curl -X POST --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/apps/<appId>/start?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"containerId":"6d9e1efdb9aad90fdb2df911f785b6aa00270e9448e75226a9a7361c8a9500cf"}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>}' \
	"https://api.resin.io/supervisor/v1/apps/<appId>/start"

GET /v1/apps/:appId

Introduced in supervisor v1.8. Returns the application running on the device The app is a JSON object that contains the following:

appId: The id of the app as per the Resin API.
commit: Application commit that is running.
imageId: The docker image of the current application build.
containerId: ID of the docker container of the running app.
env: A key-value store of the app's environment variables.

The appId must be specified in the URL.

Examples:

From the app on the device:

$ curl -X GET --header "Content-Type:application/json" \
	"$RESIN_SUPERVISOR_ADDRESS/v1/apps/<appId>?apikey=$RESIN_SUPERVISOR_API_KEY"

Response:

{"appId": 3134,"commit":"414e65cd378a69a96f403b75f14b40b55856f860","imageId":"registry.resin.io/superapp/414e65cd378a69a96f403b75f14b40b55856f860","containerId":"e5c1eace8b4e","env":{"FOO":"bar"}}

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "method": "GET"}' \
	"https://api.resin.io/supervisor/v1/apps/<appId>"

GET /v1/healthy

Added in supervisor v6.5.0.

Used internally to check whether the supervisor is running correctly, according to some heuristics that help determine whether the internal components, application updates and reporting to the Resin API are functioning.

Responds with an empty 200 response if the supervisor is healthy, or a 500 status code if something is not working correctly.

Examples:

From the app on the device:

$ curl "$RESIN_SUPERVISOR_ADDRESS/v1/healthy"

(Empty response)

Remotely via the API proxy:

$ curl -X POST --header "Content-Type:application/json" \
	--header "Authorization: Bearer <auth token>" \
	--data '{"deviceId": <deviceId>, "appId": <appId>, "method": "GET"}' \
	"https://api.resin.io/supervisor/v1/healthy"

15 KiB Raw Blame History

Interacting with the Resin Supervisor

HTTP API reference

GET /ping

Examples:

POST /v1/blink

Examples:

POST /v1/update

Request body

Examples:

POST /v1/reboot

Examples:

POST /v1/shutdown

Examples:

POST /v1/purge

Request body

Examples:

POST /v1/restart

Request body

Examples:

POST /v1/tcp-ping

Examples:

DELETE /v1/tcp-ping

Examples:

POST /v1/regenerate-api-key

Examples:

GET /v1/device

Examples:

POST /v1/apps/:appId/stop

Request body

Examples:

POST /v1/apps/:appId/start

Examples:

GET /v1/apps/:appId

Examples:

GET /v1/healthy

Examples:

15 KiB

Raw Blame History